Hygrometer



. R. B. SOMERS HYGROMETER Filed Feb. 20, 1928 June 9, 1931.

lnumffor omma Patented dune 9,1931

' tenant Y E. SQME, @F ZEELAND, MEGAN nuc'nomnrni This invention relates to hygrometers. It is an object and purpose of the present invention to provide a device of this kind to indicate the relative humidity of the atmosfi phere and to construct the same in a simple and economical manner, making use of the well-known physical fact that bodies which absorb moisture expand and contract when the moisture is removed while .materials W which are incapable of absorbing 'moisture are not edected by the presence of moisture in the vicinity thereoi.

An understanding of the invention and the physical embodiment thereof which has xproved simple, practical and economical to make may be had by reference to the following description taken in connection with the accompanying drawingm in which Fig. l is an elevation shog the opera- 20 tive mechanism of the hygrometer, it being understood that the same is normally housed from view.

Fig. 2 is an elevation of the expanding and contracting element of the hygrometer, the same beingshown in contracted position in full lines and in an expanded position in dotted lines and Fig. 3 is a iraentary enlar ed transverse section substantially on the llne of 3-3 30 of Fig. 2.

like reference characters refer. to like parts in the difierent figures of the drawings.

In the construction of a hygrometer a housing member i of usual form is provided 3 within which the expanding and contractin element which operates the indicatin bane of the hygrometer is located. This .e ement comprises a band 2 of metal of curved form which at one end is provided with an in,- turned flange 3. This end of the band 2 is permanently secured to an anchor d which in turn is permanently attached to the housing member 1 securelyanchoring it in place. At the opposite end of the band a member 5 is permanently secured by welding, soldering or otherwise and has a flange turned inwardly similar to the flange 3. From said flange of the member 5 an ear 6 projects, the purpose of which will hereinafter a pear.

At the ier concave side 0 the metal .are in direct and iediate contact with moisture. -Theexpansion of t e blocks 7 at their inner exposed sides causes the same to Application filed February 2d, 1928. Serial No. 255,526..

band 2 a consecutive series of blocks "Z oi wood or equivalent'material are located and secured in any suitable manner. The end blocks of the series bear against the inturned flange 3 and the inturned flange of the memberh. The intermediate blocks 7 have close abutting contact with each other at their sides. Holes 8 are made through the blocks for the purpose. of greatly enlarging their exposed surface area and decreasing the to thickness of. the block between all exposed surfaces. This feature is of considerable importance as it greatly adds to the sensitivity and eficiency of the apparatus. With the greater exposed surface the bloclrs will much more quickly absorb moisture from the atmosphere and the absorption of the blockwill be much more complete resulting in a quicker and more sensitive actuation and in a greater degree oi expansion. to

,rfl link 9 is pivotally connected at one end to the ear 6 and at the opposite'end to a lever 10 which is pivotally mounted on the housing member 1 at 11 at a point between its ends. The free end oi the lever 10 is formed with a gear se went l2 meshing with a small pinionl fixed on a shaft on which an indi eating hand 1% is also secured.

The blocks 7 or wood or other material, capable of absorbing moisture or vapor from the air, expand at their exsed sides on ah sonbing such moisture. ut by reason of the iactthat the outer sides of said bloclrs the metal band 2 moisture is not absorbed by such outer sides and the blocks do not expand next to the band, but expand at their inner exposed sides only. The openings 8 permit a 'more rapid absor tion of the elongate at such sides whereupon the metal band 2 is distorted and the free end portion of the expanding element moves out- Wardly with" a consequent movement of the link 9, whereupon-the'lever 10 is operated and the pointer 14 turned in proportion to the extentof the change in form or expansion of the expanding and controlling element of the device. When the moisture con- 7/ tent of the atmosphere reduces the blocks 7 give up their mo sture proportionately and contract at their inner exposed sides;' and the device returns to or toward its original position, the band 2 being of an elastic nature the-tendency of which is to return to normal position. It is, of course, understood that the band 2 could be of soft and pliable metal and a spring used to return 10 the same to a contracted position on contraction of the blocks 7. Preferably, however, the spring action required is inherent in the metal band 2.

-The construction described is very simple and economical to produce and has proved practical, efficient and accurate in service. It is economical to manufacture and is durable.- The invention is defined in the appended claims and is to be consid 2o ered comprehensive of all forms of structure coming within their scope.

I claim: 1. In a hygrometer, a band of flexible relatively non-expansible material, flange means at either end of the band and a plurality of blocks of absorptive expansible material laid end to end ad'acent saidband, the respective end blocks a utting the flange means of said band, said blocks having openings whereby their exposed surface is increased.

' 2. In a hygrometer having a housing, a curved metal band adapted to be anchored at one end to the hygrometer housing, a

5 plurality of moisture absorbing blocks located at the inner concave side of the band, having exposed inner sides, tightly abutting ends and outer sides contacting against the band and means for holding the end blocks 40 of the plurality of blocks againstx movement relative to the band.

3. A device of the class described comprising, a supporting member, a curved band of metal fastened at one end to the said sup- 5 ortin member, flan es extending inwardly rom t e ends of said band and a plurality of tapered blocks capable of absorbing moisture from the air laced against the inner side of the band with their tapered sides in so tight abutting relationship, said blocks extending continuously from one flange to the other.

In testimony whereof I afirlx my si ature. '1 ROY B. SO ERS.- 

